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 * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
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 *
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package com.nulldev.util.graphics.renderIt.ginterfaces.marlin.impl.pisces;

import java.util.Arrays;

import com.nulldev.util.graphics.renderIt.ginterfaces.marlin.impl.pisces.TransformingPathConsumer2D.CurveBasicMonotonizer;
import com.nulldev.util.graphics.renderIt.ginterfaces.marlin.impl.pisces.TransformingPathConsumer2D.CurveClipSplitter;

import sun.awt.geom.PathConsumer2D;

/**
 * The <code>Dasher</code> class takes a series of linear commands
 * (<code>moveTo</code>, <code>lineTo</code>, <code>close</code> and
 * <code>end</code>) and breaks them into smaller segments according to a dash
 * pattern array and a starting dash phase.
 *
 * <p>
 * Issues: in J2Se, a zero length dash segment as drawn as a very short dash,
 * whereas Pisces does not draw anything. The PostScript semantics are unclear.
 *
 */
final class Dasher implements PathConsumer2D, MarlinConst {

	/* huge circle with radius ~ 2E9 only needs 12 subdivision levels */
	static final int REC_LIMIT = 16;
	static final float CURVE_LEN_ERR = MarlinProperties.getCurveLengthError(); // 0.01
	static final float MIN_T_INC = 1.0f / (1 << REC_LIMIT);

	static final float EPS = 1e-6f;

	// More than 24 bits of mantissa means we can no longer accurately
	// measure the number of times cycled through the dash array so we
	// punt and override the phase to just be 0 past that point.
	static final float MAX_CYCLES = 16000000.0f;

	private PathConsumer2D out;
	private float[] dash;
	private int dashLen;
	private float startPhase;
	private boolean startDashOn;
	private int startIdx;

	private boolean starting;
	private boolean needsMoveTo;

	private int idx;
	private boolean dashOn;
	private float phase;

	// The starting point of the path
	private float sx0, sy0;
	// the current point
	private float cx0, cy0;

	// temporary storage for the current curve
	private final float[] curCurvepts;

	// per-thread renderer context
	final RendererContext rdrCtx;

	// flag to recycle dash array copy
	boolean recycleDashes;

	// We don't emit the first dash right away. If we did, caps would be
	// drawn on it, but we need joins to be drawn if there's a closePath()
	// So, we store the path elements that make up the first dash in the
	// buffer below.
	private float[] firstSegmentsBuffer; // dynamic array
	private int firstSegidx;

	// dashes ref (dirty)
	final FloatArrayCache.Reference dashes_ref;
	// firstSegmentsBuffer ref (dirty)
	final FloatArrayCache.Reference firstSegmentsBuffer_ref;

	// Bounds of the drawing region, at pixel precision.
	private float[] clipRect;

	// the outcode of the current point
	private int cOutCode = 0;

	private boolean subdivide = DO_CLIP_SUBDIVIDER;

	private final LengthIterator li = new LengthIterator();

	private final CurveClipSplitter curveSplitter;

	private float cycleLen;
	private boolean outside;
	private float totalSkipLen;

	/**
	 * Constructs a <code>Dasher</code>.
	 * 
	 * @param rdrCtx per-thread renderer context
	 */
	Dasher(final RendererContext rdrCtx) {
		this.rdrCtx = rdrCtx;

		dashes_ref = rdrCtx.newDirtyFloatArrayRef(INITIAL_ARRAY); // 1K

		firstSegmentsBuffer_ref = rdrCtx.newDirtyFloatArrayRef(INITIAL_ARRAY); // 1K
		firstSegmentsBuffer = firstSegmentsBuffer_ref.initial;

		// we need curCurvepts to be able to contain 2 curves because when
		// dashing curves, we need to subdivide it
		curCurvepts = new float[8 * 2];

		this.curveSplitter = rdrCtx.curveClipSplitter;
	}

	/**
	 * Initialize the <code>Dasher</code>.
	 *
	 * @param out           an output <code>PathConsumer2D</code>.
	 * @param dash          an array of <code>float</code>s containing the dash
	 *                      pattern
	 * @param dashLen       length of the given dash array
	 * @param phase         a <code>float</code> containing the dash phase
	 * @param recycleDashes true to indicate to recycle the given dash array
	 * @return this instance
	 */
	Dasher init(final PathConsumer2D out, final float[] dash, final int dashLen, float phase, final boolean recycleDashes) {
		this.out = out;

		// Normalize so 0 <= phase < dash[0]
		int sidx = 0;
		dashOn = true;

		// note: BasicStroke constructor checks dash elements and sum > 0
		float sum = 0.0f;
		for (int i = 0; i < dashLen; i++) {
			sum += dash[i];
		}
		this.cycleLen = sum;

		float cycles = phase / sum;
		if (phase < 0.0f) {
			if (-cycles >= MAX_CYCLES) {
				phase = 0.0f;
			} else {
				int fullcycles = FloatMath.floor_int(-cycles);
				if ((fullcycles & dashLen & 1) != 0) {
					dashOn = !dashOn;
				}
				phase += fullcycles * sum;
				while (phase < 0.0f) {
					if (--sidx < 0) {
						sidx = dashLen - 1;
					}
					phase += dash[sidx];
					dashOn = !dashOn;
				}
			}
		} else if (phase > 0.0f) {
			if (cycles >= MAX_CYCLES) {
				phase = 0.0f;
			} else {
				int fullcycles = FloatMath.floor_int(cycles);
				if ((fullcycles & dashLen & 1) != 0) {
					dashOn = !dashOn;
				}
				phase -= fullcycles * sum;
				float d;
				while (phase >= (d = dash[sidx])) {
					phase -= d;
					sidx = (sidx + 1) % dashLen;
					dashOn = !dashOn;
				}
			}
		}

		this.dash = dash;
		this.dashLen = dashLen;
		this.phase = phase;
		this.startPhase = phase;
		this.startDashOn = dashOn;
		this.startIdx = sidx;
		this.starting = true;
		this.needsMoveTo = false;
		this.firstSegidx = 0;

		this.recycleDashes = recycleDashes;

		if (rdrCtx.doClip) {
			this.clipRect = rdrCtx.clipRect;
		} else {
			this.clipRect = null;
			this.cOutCode = 0;
		}
		return this; // fluent API
	}

	/**
	 * Disposes this dasher: clean up before reusing this instance
	 */
	void dispose() {
		if (DO_CLEAN_DIRTY) {
			// Force zero-fill dirty arrays:
			Arrays.fill(curCurvepts, 0.0f);
		}
		// Return arrays:
		if (recycleDashes) {
			dash = dashes_ref.putArray(dash);
		}
		firstSegmentsBuffer = firstSegmentsBuffer_ref.putArray(firstSegmentsBuffer);
	}

	float[] copyDashArray(final float[] dashes) {
		final int len = dashes.length;
		final float[] newDashes;
		if (len <= MarlinConst.INITIAL_ARRAY) {
			newDashes = dashes_ref.initial;
		} else {
			if (DO_STATS) {
				rdrCtx.stats.stat_array_dasher_dasher.add(len);
			}
			newDashes = dashes_ref.getArray(len);
		}
		System.arraycopy(dashes, 0, newDashes, 0, len);
		return newDashes;
	}

	@Override
	public void moveTo(final float x0, final float y0) {
		if (firstSegidx != 0) {
			out.moveTo(sx0, sy0);
			emitFirstSegments();
		}
		this.needsMoveTo = true;
		this.idx = startIdx;
		this.dashOn = this.startDashOn;
		this.phase = this.startPhase;
		this.cx0 = x0;
		this.cy0 = y0;

		// update starting point:
		this.sx0 = x0;
		this.sy0 = y0;
		this.starting = true;

		if (clipRect != null) {
			final int outcode = Helpers.outcode(x0, y0, clipRect);
			this.cOutCode = outcode;
			this.outside = false;
			this.totalSkipLen = 0.0f;
		}
	}

	private void emitSeg(float[] buf, int off, int type) {
		switch (type) {
			case 4:
				out.lineTo(buf[off], buf[off + 1]);
				return;
			case 8:
				out.curveTo(buf[off], buf[off + 1], buf[off + 2], buf[off + 3], buf[off + 4], buf[off + 5]);
				return;
			case 6:
				out.quadTo(buf[off], buf[off + 1], buf[off + 2], buf[off + 3]);
				return;
			default:
		}
	}

	private void emitFirstSegments() {
		final float[] fSegBuf = firstSegmentsBuffer;

		for (int i = 0, len = firstSegidx; i < len;) {
			int type = (int) fSegBuf[i];
			emitSeg(fSegBuf, i + 1, type);
			i += (type - 1);
		}
		firstSegidx = 0;
	}

	// precondition: pts must be in relative coordinates (relative to x0,y0)
	private void goTo(final float[] pts, final int off, final int type, final boolean on) {
		final int index = off + type;
		final float x = pts[index - 4];
		final float y = pts[index - 3];

		if (on) {
			if (starting) {
				goTo_starting(pts, off, type);
			} else {
				if (needsMoveTo) {
					needsMoveTo = false;
					out.moveTo(cx0, cy0);
				}
				emitSeg(pts, off, type);
			}
		} else {
			if (starting) {
				// low probability test (hotspot)
				starting = false;
			}
			needsMoveTo = true;
		}
		this.cx0 = x;
		this.cy0 = y;
	}

	private void goTo_starting(final float[] pts, final int off, final int type) {
		int len = type - 1; // - 2 + 1
		int segIdx = firstSegidx;
		float[] buf = firstSegmentsBuffer;

		if (segIdx + len > buf.length) {
			if (DO_STATS) {
				rdrCtx.stats.stat_array_dasher_firstSegmentsBuffer.add(segIdx + len);
			}
			firstSegmentsBuffer = buf = firstSegmentsBuffer_ref.widenArray(buf, segIdx, segIdx + len);
		}
		buf[segIdx++] = type;
		len--;
		// small arraycopy (2, 4 or 6) but with offset:
		System.arraycopy(pts, off, buf, segIdx, len);
		firstSegidx = segIdx + len;
	}

	@Override
	public void lineTo(final float x1, final float y1) {
		final int outcode0 = this.cOutCode;

		if (clipRect != null) {
			final int outcode1 = Helpers.outcode(x1, y1, clipRect);

			// Should clip
			final int orCode = (outcode0 | outcode1);

			if (orCode != 0) {
				final int sideCode = outcode0 & outcode1;

				// basic rejection criteria:
				if (sideCode == 0) {
					// overlap clip:
					if (subdivide) {
						// avoid reentrance
						subdivide = false;
						// subdivide curve => callback with subdivided parts:
						boolean ret = curveSplitter.splitLine(cx0, cy0, x1, y1, orCode, this);
						// reentrance is done:
						subdivide = true;
						if (ret) {
							return;
						}
					}
					// already subdivided so render it
				} else {
					this.cOutCode = outcode1;
					skipLineTo(x1, y1);
					return;
				}
			}

			this.cOutCode = outcode1;

			if (this.outside) {
				this.outside = false;
				// Adjust current index, phase & dash:
				skipLen();
			}
		}
		_lineTo(x1, y1);
	}

	private void _lineTo(final float x1, final float y1) {
		final float dx = x1 - cx0;
		final float dy = y1 - cy0;

		float len = dx * dx + dy * dy;
		if (len == 0.0f) {
			return;
		}
		len = (float) Math.sqrt(len);

		// The scaling factors needed to get the dx and dy of the
		// transformed dash segments.
		final float cx = dx / len;
		final float cy = dy / len;

		final float[] _curCurvepts = curCurvepts;
		final float[] _dash = dash;
		final int _dashLen = this.dashLen;

		int _idx = idx;
		boolean _dashOn = dashOn;
		float _phase = phase;

		float leftInThisDashSegment, rem;

		while (true) {
			leftInThisDashSegment = _dash[_idx] - _phase;
			rem = len - leftInThisDashSegment;

			if (rem <= EPS) {
				_curCurvepts[0] = x1;
				_curCurvepts[1] = y1;

				goTo(_curCurvepts, 0, 4, _dashOn);

				// Advance phase within current dash segment
				_phase += len;

				// compare values using epsilon:
				if (Math.abs(rem) <= EPS) {
					_phase = 0.0f;
					_idx = (_idx + 1) % _dashLen;
					_dashOn = !_dashOn;
				}
				break;
			}

			_curCurvepts[0] = cx0 + leftInThisDashSegment * cx;
			_curCurvepts[1] = cy0 + leftInThisDashSegment * cy;

			goTo(_curCurvepts, 0, 4, _dashOn);

			len = rem;
			// Advance to next dash segment
			_idx = (_idx + 1) % _dashLen;
			_dashOn = !_dashOn;
			_phase = 0.0f;
		}
		// Save local state:
		idx = _idx;
		dashOn = _dashOn;
		phase = _phase;
	}

	private void skipLineTo(final float x1, final float y1) {
		final float dx = x1 - cx0;
		final float dy = y1 - cy0;

		float len = dx * dx + dy * dy;
		if (len != 0.0f) {
			len = (float) Math.sqrt(len);
		}

		// Accumulate skipped length:
		this.outside = true;
		this.totalSkipLen += len;

		// Fix initial move:
		this.needsMoveTo = true;
		this.starting = false;

		this.cx0 = x1;
		this.cy0 = y1;
	}

	public void skipLen() {
		float len = this.totalSkipLen;
		this.totalSkipLen = 0.0f;

		final float[] _dash = dash;
		final int _dashLen = this.dashLen;

		int _idx = idx;
		boolean _dashOn = dashOn;
		float _phase = phase;

		// -2 to ensure having 2 iterations of the post-loop
		// to compensate the remaining phase
		final long fullcycles = (long) Math.floor(len / cycleLen) - 2L;

		if (fullcycles > 0L) {
			len -= cycleLen * fullcycles;

			final long iterations = fullcycles * _dashLen;
			_idx = (int) (iterations + _idx) % _dashLen;
			_dashOn = (iterations + (_dashOn ? 1L : 0L) & 1L) == 1L;
		}

		float leftInThisDashSegment, rem;

		while (true) {
			leftInThisDashSegment = _dash[_idx] - _phase;
			rem = len - leftInThisDashSegment;

			if (rem <= EPS) {
				// Advance phase within current dash segment
				_phase += len;

				// compare values using epsilon:
				if (Math.abs(rem) <= EPS) {
					_phase = 0.0f;
					_idx = (_idx + 1) % _dashLen;
					_dashOn = !_dashOn;
				}
				break;
			}

			len = rem;
			// Advance to next dash segment
			_idx = (_idx + 1) % _dashLen;
			_dashOn = !_dashOn;
			_phase = 0.0f;
		}
		// Save local state:
		idx = _idx;
		dashOn = _dashOn;
		phase = _phase;
	}

	// preconditions: curCurvepts must be an array of length at least 2 * type,
	// that contains the curve we want to dash in the first type elements
	private void somethingTo(final int type) {
		final float[] _curCurvepts = curCurvepts;
		if (pointCurve(_curCurvepts, type)) {
			return;
		}
		final LengthIterator _li = li;
		final float[] _dash = dash;
		final int _dashLen = this.dashLen;

		_li.initializeIterationOnCurve(_curCurvepts, type);

		int _idx = idx;
		boolean _dashOn = dashOn;
		float _phase = phase;

		// initially the current curve is at curCurvepts[0...type]
		int curCurveoff = 0;
		float prevT = 0.0f;
		float t;
		float leftInThisDashSegment = _dash[_idx] - _phase;

		while ((t = _li.next(leftInThisDashSegment)) < 1.0f) {
			if (t != 0.0f) {
				Helpers.subdivideAt((t - prevT) / (1.0f - prevT), _curCurvepts, curCurveoff, _curCurvepts, 0, type);
				prevT = t;
				goTo(_curCurvepts, 2, type, _dashOn);
				curCurveoff = type;
			}
			// Advance to next dash segment
			_idx = (_idx + 1) % _dashLen;
			_dashOn = !_dashOn;
			_phase = 0.0f;
			leftInThisDashSegment = _dash[_idx];
		}

		goTo(_curCurvepts, curCurveoff + 2, type, _dashOn);

		_phase += _li.lastSegLen();

		// compare values using epsilon:
		if (_phase + EPS >= _dash[_idx]) {
			_phase = 0.0f;
			_idx = (_idx + 1) % _dashLen;
			_dashOn = !_dashOn;
		}
		// Save local state:
		idx = _idx;
		dashOn = _dashOn;
		phase = _phase;

		// reset LengthIterator:
		_li.reset();
	}

	private void skipSomethingTo(final int type) {
		final float[] _curCurvepts = curCurvepts;
		if (pointCurve(_curCurvepts, type)) {
			return;
		}
		final LengthIterator _li = li;

		_li.initializeIterationOnCurve(_curCurvepts, type);

		// In contrary to somethingTo(),
		// just estimate properly the curve length:
		final float len = _li.totalLength();

		// Accumulate skipped length:
		this.outside = true;
		this.totalSkipLen += len;

		// Fix initial move:
		this.needsMoveTo = true;
		this.starting = false;
	}

	private static boolean pointCurve(final float[] curve, final int type) {
		for (int i = 2; i < type; i++) {
			if (curve[i] != curve[i - 2]) {
				return false;
			}
		}
		return true;
	}

	// Objects of this class are used to iterate through curves. They return
	// t values where the left side of the curve has a specified length.
	// It does this by subdividing the input curve until a certain error
	// condition has been met. A recursive subdivision procedure would
	// return as many as 1<<limit curves, but this is an iterator and we
	// don't need all the curves all at once, so what we carry out a
	// lazy inorder traversal of the recursion tree (meaning we only move
	// through the tree when we need the next subdivided curve). This saves
	// us a lot of memory because at any one time we only need to store
	// limit+1 curves - one for each level of the tree + 1.
	// NOTE: the way we do things here is not enough to traverse a general
	// tree; however, the trees we are interested in have the property that
	// every non leaf node has exactly 2 children
	static final class LengthIterator {
		// Holds the curves at various levels of the recursion. The root
		// (i.e. the original curve) is at recCurveStack[0] (but then it
		// gets subdivided, the left half is put at 1, so most of the time
		// only the right half of the original curve is at 0)
		private final float[][] recCurveStack; // dirty
		// sidesRight[i] indicates whether the node at level i+1 in the path from
		// the root to the current leaf is a left or right child of its parent.
		private final boolean[] sidesRight; // dirty
		private int curveType;
		// lastT and nextT delimit the current leaf.
		private float nextT;
		private float lenAtNextT;
		private float lastT;
		private float lenAtLastT;
		private float lenAtLastSplit;
		private float lastSegLen;
		// the current level in the recursion tree. 0 is the root. limit
		// is the deepest possible leaf.
		private int recLevel;
		private boolean done;

		// the lengths of the lines of the control polygon. Only its first
		// curveType/2 - 1 elements are valid. This is an optimization. See
		// next() for more detail.
		private final float[] curLeafCtrlPolyLengths = new float[3];

		LengthIterator() {
			this.recCurveStack = new float[REC_LIMIT + 1][8];
			this.sidesRight = new boolean[REC_LIMIT];
			// if any methods are called without first initializing this object
			// on a curve, we want it to fail ASAP.
			this.nextT = Float.MAX_VALUE;
			this.lenAtNextT = Float.MAX_VALUE;
			this.lenAtLastSplit = Float.MIN_VALUE;
			this.recLevel = Integer.MIN_VALUE;
			this.lastSegLen = Float.MAX_VALUE;
			this.done = true;
		}

		/**
		 * Reset this LengthIterator.
		 */
		void reset() {
			// keep data dirty
			// as it appears not useful to reset data:
			if (DO_CLEAN_DIRTY) {
				final int recLimit = recCurveStack.length - 1;
				for (int i = recLimit; i >= 0; i--) {
					Arrays.fill(recCurveStack[i], 0.0f);
				}
				Arrays.fill(sidesRight, false);
				Arrays.fill(curLeafCtrlPolyLengths, 0.0f);
				Arrays.fill(nextRoots, 0.0f);
				Arrays.fill(flatLeafCoefCache, 0.0f);
				flatLeafCoefCache[2] = -1.0f;
			}
		}

		void initializeIterationOnCurve(final float[] pts, final int type) {
			// optimize arraycopy (8 values faster than 6 = type):
			System.arraycopy(pts, 0, recCurveStack[0], 0, 8);
			this.curveType = type;
			this.recLevel = 0;
			this.lastT = 0.0f;
			this.lenAtLastT = 0.0f;
			this.nextT = 0.0f;
			this.lenAtNextT = 0.0f;
			goLeft(); // initializes nextT and lenAtNextT properly
			this.lenAtLastSplit = 0.0f;
			if (recLevel > 0) {
				this.sidesRight[0] = false;
				this.done = false;
			} else {
				// the root of the tree is a leaf so we're done.
				this.sidesRight[0] = true;
				this.done = true;
			}
			this.lastSegLen = 0.0f;
		}

		// 0 == false, 1 == true, -1 == invalid cached value.
		private int cachedHaveLowAcceleration = -1;

		private boolean haveLowAcceleration(final float err) {
			if (cachedHaveLowAcceleration == -1) {
				final float len1 = curLeafCtrlPolyLengths[0];
				final float len2 = curLeafCtrlPolyLengths[1];
				// the test below is equivalent to !within(len1/len2, 1, err).
				// It is using a multiplication instead of a division, so it
				// should be a bit faster.
				if (!Helpers.within(len1, len2, err * len2)) {
					cachedHaveLowAcceleration = 0;
					return false;
				}
				if (curveType == 8) {
					final float len3 = curLeafCtrlPolyLengths[2];
					// if len1 is close to 2 and 2 is close to 3, that probably
					// means 1 is close to 3 so the second part of this test might
					// not be needed, but it doesn't hurt to include it.
					final float errLen3 = err * len3;
					if (!(Helpers.within(len2, len3, errLen3) && Helpers.within(len1, len3, errLen3))) {
						cachedHaveLowAcceleration = 0;
						return false;
					}
				}
				cachedHaveLowAcceleration = 1;
				return true;
			}

			return (cachedHaveLowAcceleration == 1);
		}

		// we want to avoid allocations/gc so we keep this array so we
		// can put roots in it,
		private final float[] nextRoots = new float[4];

		// caches the coefficients of the current leaf in its flattened
		// form (see inside next() for what that means). The cache is
		// invalid when it's third element is negative, since in any
		// valid flattened curve, this would be >= 0.
		private final float[] flatLeafCoefCache = new float[]
			{ 0.0f, 0.0f, -1.0f, 0.0f };

		// returns the t value where the remaining curve should be split in
		// order for the left subdivided curve to have length len. If len
		// is >= than the length of the uniterated curve, it returns 1.
		float next(final float len) {
			final float targetLength = lenAtLastSplit + len;
			while (lenAtNextT < targetLength) {
				if (done) {
					lastSegLen = lenAtNextT - lenAtLastSplit;
					return 1.0f;
				}
				goToNextLeaf();
			}
			lenAtLastSplit = targetLength;
			final float leaflen = lenAtNextT - lenAtLastT;
			float t = (targetLength - lenAtLastT) / leaflen;

			// cubicRootsInAB is a fairly expensive call, so we just don't do it
			// if the acceleration in this section of the curve is small enough.
			if (!haveLowAcceleration(0.05f)) {
				// We flatten the current leaf along the x axis, so that we're
				// left with a, b, c which define a 1D Bezier curve. We then
				// solve this to get the parameter of the original leaf that
				// gives us the desired length.
				final float[] _flatLeafCoefCache = flatLeafCoefCache;

				if (_flatLeafCoefCache[2] < 0.0f) {
					float x = curLeafCtrlPolyLengths[0], y = x + curLeafCtrlPolyLengths[1];
					if (curveType == 8) {
						float z = y + curLeafCtrlPolyLengths[2];
						_flatLeafCoefCache[0] = 3.0f * (x - y) + z;
						_flatLeafCoefCache[1] = 3.0f * (y - 2.0f * x);
						_flatLeafCoefCache[2] = 3.0f * x;
						_flatLeafCoefCache[3] = -z;
					} else if (curveType == 6) {
						_flatLeafCoefCache[0] = 0.0f;
						_flatLeafCoefCache[1] = y - 2.0f * x;
						_flatLeafCoefCache[2] = 2.0f * x;
						_flatLeafCoefCache[3] = -y;
					}
				}
				float a = _flatLeafCoefCache[0];
				float b = _flatLeafCoefCache[1];
				float c = _flatLeafCoefCache[2];
				float d = t * _flatLeafCoefCache[3];

				// we use cubicRootsInAB here, because we want only roots in 0, 1,
				// and our quadratic root finder doesn't filter, so it's just a
				// matter of convenience.
				final int n = Helpers.cubicRootsInAB(a, b, c, d, nextRoots, 0, 0.0f, 1.0f);
				if (n == 1 && !Float.isNaN(nextRoots[0])) {
					t = nextRoots[0];
				}
			}
			// t is relative to the current leaf, so we must make it a valid parameter
			// of the original curve.
			t = t * (nextT - lastT) + lastT;
			if (t >= 1.0f) {
				t = 1.0f;
				done = true;
			}
			// even if done = true, if we're here, that means targetLength
			// is equal to, or very, very close to the total length of the
			// curve, so lastSegLen won't be too high. In cases where len
			// overshoots the curve, this method will exit in the while
			// loop, and lastSegLen will still be set to the right value.
			lastSegLen = len;
			return t;
		}

		float totalLength() {
			while (!done) {
				goToNextLeaf();
			}
			// reset LengthIterator:
			reset();

			return lenAtNextT;
		}

		float lastSegLen() {
			return lastSegLen;
		}

		// go to the next leaf (in an inorder traversal) in the recursion tree
		// preconditions: must be on a leaf, and that leaf must not be the root.
		private void goToNextLeaf() {
			// We must go to the first ancestor node that has an unvisited
			// right child.
			final boolean[] _sides = sidesRight;
			int _recLevel = recLevel;
			_recLevel--;

			while (_sides[_recLevel]) {
				if (_recLevel == 0) {
					recLevel = 0;
					done = true;
					return;
				}
				_recLevel--;
			}

			_sides[_recLevel] = true;
			// optimize arraycopy (8 values faster than 6 = type):
			System.arraycopy(recCurveStack[_recLevel++], 0, recCurveStack[_recLevel], 0, 8);
			recLevel = _recLevel;
			goLeft();
		}

		// go to the leftmost node from the current node. Return its length.
		private void goLeft() {
			final float len = onLeaf();
			if (len >= 0.0f) {
				lastT = nextT;
				lenAtLastT = lenAtNextT;
				nextT += (1 << (REC_LIMIT - recLevel)) * MIN_T_INC;
				lenAtNextT += len;
				// invalidate caches
				flatLeafCoefCache[2] = -1.0f;
				cachedHaveLowAcceleration = -1;
			} else {
				Helpers.subdivide(recCurveStack[recLevel], recCurveStack[recLevel + 1], recCurveStack[recLevel], curveType);

				sidesRight[recLevel] = false;
				recLevel++;
				goLeft();
			}
		}

		// this is a bit of a hack. It returns -1 if we're not on a leaf, and
		// the length of the leaf if we are on a leaf.
		private float onLeaf() {
			final float[] curve = recCurveStack[recLevel];
			final int _curveType = curveType;
			float polyLen = 0.0f;

			float x0 = curve[0], y0 = curve[1];
			for (int i = 2; i < _curveType; i += 2) {
				final float x1 = curve[i], y1 = curve[i + 1];
				final float len = Helpers.linelen(x0, y0, x1, y1);
				polyLen += len;
				curLeafCtrlPolyLengths[(i >> 1) - 1] = len;
				x0 = x1;
				y0 = y1;
			}

			final float lineLen = Helpers.linelen(curve[0], curve[1], x0, y0);

			if ((polyLen - lineLen) < CURVE_LEN_ERR || recLevel == REC_LIMIT) {
				return (polyLen + lineLen) / 2.0f;
			}
			return -1.0f;
		}
	}

	@Override
	public void curveTo(final float x1, final float y1, final float x2, final float y2, final float x3, final float y3) {
		final int outcode0 = this.cOutCode;

		if (clipRect != null) {
			final int outcode1 = Helpers.outcode(x1, y1, clipRect);
			final int outcode2 = Helpers.outcode(x2, y2, clipRect);
			final int outcode3 = Helpers.outcode(x3, y3, clipRect);

			// Should clip
			final int orCode = (outcode0 | outcode1 | outcode2 | outcode3);
			if (orCode != 0) {
				final int sideCode = outcode0 & outcode1 & outcode2 & outcode3;

				// basic rejection criteria:
				if (sideCode == 0) {
					// overlap clip:
					if (subdivide) {
						// avoid reentrance
						subdivide = false;
						// subdivide curve => callback with subdivided parts:
						boolean ret = curveSplitter.splitCurve(cx0, cy0, x1, y1, x2, y2, x3, y3, orCode, this);
						// reentrance is done:
						subdivide = true;
						if (ret) {
							return;
						}
					}
					// already subdivided so render it
				} else {
					this.cOutCode = outcode3;
					skipCurveTo(x1, y1, x2, y2, x3, y3);
					return;
				}
			}

			this.cOutCode = outcode3;

			if (this.outside) {
				this.outside = false;
				// Adjust current index, phase & dash:
				skipLen();
			}
		}
		_curveTo(x1, y1, x2, y2, x3, y3);
	}

	private void _curveTo(final float x1, final float y1, final float x2, final float y2, final float x3, final float y3) {
		final float[] _curCurvepts = curCurvepts;

		// monotonize curve:
		final CurveBasicMonotonizer monotonizer = rdrCtx.monotonizer.curve(cx0, cy0, x1, y1, x2, y2, x3, y3);

		final int nSplits = monotonizer.nbSplits;
		final float[] mid = monotonizer.middle;

		for (int i = 0, off = 0; i <= nSplits; i++, off += 6) {
			// optimize arraycopy (8 values faster than 6 = type):
			System.arraycopy(mid, off, _curCurvepts, 0, 8);

			somethingTo(8);
		}
	}

	private void skipCurveTo(final float x1, final float y1, final float x2, final float y2, final float x3, final float y3) {
		final float[] _curCurvepts = curCurvepts;
		_curCurvepts[0] = cx0;
		_curCurvepts[1] = cy0;
		_curCurvepts[2] = x1;
		_curCurvepts[3] = y1;
		_curCurvepts[4] = x2;
		_curCurvepts[5] = y2;
		_curCurvepts[6] = x3;
		_curCurvepts[7] = y3;

		skipSomethingTo(8);

		this.cx0 = x3;
		this.cy0 = y3;
	}

	@Override
	public void quadTo(final float x1, final float y1, final float x2, final float y2) {
		final int outcode0 = this.cOutCode;

		if (clipRect != null) {
			final int outcode1 = Helpers.outcode(x1, y1, clipRect);
			final int outcode2 = Helpers.outcode(x2, y2, clipRect);

			// Should clip
			final int orCode = (outcode0 | outcode1 | outcode2);
			if (orCode != 0) {
				final int sideCode = outcode0 & outcode1 & outcode2;

				// basic rejection criteria:
				if (sideCode == 0) {
					// overlap clip:
					if (subdivide) {
						// avoid reentrance
						subdivide = false;
						// subdivide curve => call lineTo() with subdivided curves:
						boolean ret = curveSplitter.splitQuad(cx0, cy0, x1, y1, x2, y2, orCode, this);
						// reentrance is done:
						subdivide = true;
						if (ret) {
							return;
						}
					}
					// already subdivided so render it
				} else {
					this.cOutCode = outcode2;
					skipQuadTo(x1, y1, x2, y2);
					return;
				}
			}

			this.cOutCode = outcode2;

			if (this.outside) {
				this.outside = false;
				// Adjust current index, phase & dash:
				skipLen();
			}
		}
		_quadTo(x1, y1, x2, y2);
	}

	private void _quadTo(final float x1, final float y1, final float x2, final float y2) {
		final float[] _curCurvepts = curCurvepts;

		// monotonize quad:
		final CurveBasicMonotonizer monotonizer = rdrCtx.monotonizer.quad(cx0, cy0, x1, y1, x2, y2);

		final int nSplits = monotonizer.nbSplits;
		final float[] mid = monotonizer.middle;

		for (int i = 0, off = 0; i <= nSplits; i++, off += 4) {
			// optimize arraycopy (8 values faster than 6 = type):
			System.arraycopy(mid, off, _curCurvepts, 0, 8);

			somethingTo(6);
		}
	}

	private void skipQuadTo(final float x1, final float y1, final float x2, final float y2) {
		final float[] _curCurvepts = curCurvepts;
		_curCurvepts[0] = cx0;
		_curCurvepts[1] = cy0;
		_curCurvepts[2] = x1;
		_curCurvepts[3] = y1;
		_curCurvepts[4] = x2;
		_curCurvepts[5] = y2;

		skipSomethingTo(6);

		this.cx0 = x2;
		this.cy0 = y2;
	}

	@Override
	public void closePath() {
		if (cx0 != sx0 || cy0 != sy0) {
			lineTo(sx0, sy0);
		}
		if (firstSegidx != 0) {
			if (!dashOn || needsMoveTo) {
				out.moveTo(sx0, sy0);
			}
			emitFirstSegments();
		}
		moveTo(sx0, sy0);
	}

	@Override
	public void pathDone() {
		if (firstSegidx != 0) {
			out.moveTo(sx0, sy0);
			emitFirstSegments();
		}
		out.pathDone();

		// Dispose this instance:
		dispose();
	}

	@Override
	public long getNativeConsumer() {
		throw new InternalError("Dasher does not use a native consumer");
	}
}
